Pulse-Width Modulation

Pulse-width Modulation During Pedicle Screw Stimulation

The overarching aim of this project is to modulate the pulse-width during stimulation of pedicle screws and record the response thresholds associated with each PWM setting. During this initial phase of the investigation, no further data will be collected.

Study Overview

• Status: Recruiting
• Conditions: Spinal Stenosis; Spinal Fusion
• Intervention / Treatment: Diagnostic test: Pulse width modulation

Detailed Description

In vivo electrical stimulation of pedicle screws is a well-documented modality for evaluating potential breach of the pedicle wall. However, previous research has focused primarily on the stimulation threshold intensity required to elicit a neurophysiological response. Other stimulation parameters, such as pulse-width, remain uninvestigated. The goal is to obtain data on the pulse-width vs. CMAP relationship.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Beverly Allen, BS; Phone Number: 6036179909; Email: Beverly..A.Allen@hitchcock.org

Study Locations

• United States
  • New Hampshire
    • Lebanon, New Hampshire, United States, 03677
      • Recruiting
      • Dartmouth-Health
      • Contact: Beverly Allen, BS; Phone Number: 603-653-9021; Email: Beverly.A.Allen@hitchcock.org
      • Principal Investigator: Linton Evans, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• A patient will be eligible for study participation once they have been booked for a surgery involving pedicle screw placement and intraoperative neuromonitoring.

Exclusion Criteria:

• The study excludes neonates, minors, pregnant women, prisoners and cognitively impaired patients.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pedicle Screw Stimulation Arm	Diagnostic test: Pulse width modulation; Will be stimulating the pedicle screws utilizing three different pulse-width settings, 0.4 milliseconds, 0.2 milliseconds, and 0.05 milliseconds.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CMAP response under three different pulse-width settings	Upon completion of the pedicle screw placements, each screw will be stimulated utilizing three different pulse-width settings, 0.4 milliseconds, 0.2 milliseconds, and 0.05 milliseconds. The stimulation intensity required to elicit a compound muscle action potential (CMAP) will be recorded for each pulse-width parameter. This is measured in microvolts (uV).	Within operating room upon completion of pedicle screw placement. 1 day

Collaborators and Investigators

• Sponsor: Dartmouth-Hitchcock Medical Center
• Investigators: Principal Investigator: Linton Evans, Dr., Dartmouth-Hitchcock Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2023
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: November 1, 2023
• First Submitted That Met QC Criteria: November 1, 2023
• First Posted (Actual): November 7, 2023

Study Record Updates

• Last Update Posted (Estimated): June 5, 2025
• Last Update Submitted That Met QC Criteria: June 3, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Bone Diseases; Musculoskeletal Diseases; Spinal Diseases; Spinal Stenosis
• Other Study ID Numbers: STUDY02001964

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No